A US icebreaker was dispatched Sunday to assist an icebound Russian research ship and Chinese vessel trapped during a rescue bid in Antarctica, as the leader of a group airlifted to safety rejected criticism of their expedition.

The US Coast Guard's Polar Star accepted an Australian request to go to the aid of the marooned Russian ship Akademik Shokalskiy which has been beset by ice since December 24.

It will also aid the Chinese icebreaker Xue Long which was involved in a dramatic helicopter rescue of the Shokalskiy's 52 passengers on Thursday.

The Xue Long has become trapped itself, with China vowing "all-out efforts" to assist the ship which is surrounded by ice of up to four metres thick and is stuck 21 kilometres from open water, according to state news agency Xinhua which has reporters on board.

China's Antarctic division director Qu Tanzhou said the Xue Long may attempt to chop itself free of the ice on Monday if conditions permit, with a massive iceberg expected to move out of its path.

"Weather forecasts and ice monitoring show favourable weather conditions may appear on Monday, which may bring winds to blow the ice floe away, providing a good opportunity for Xue Long to sail out," Qu told the China Daily newspaper.

If that was not possible and other rescue plans failed, leaving the ship stranded "for a very long time, which is very rare indeed, then we'll have to evacuate the people onboard and leave the vessel there," he added.

Xue Long's mission -- China's 30th to the Antarctic continent -- which included construction of a new research base, site inspection for another and a range of scientific work, will now have to be revised, Qu said.

The Polar Star, which left the US in early December to clear a channel for ships resupplying McMurdo Station research base, left Sydney Sunday with provisions, according to the Australian Maritime Safety Authority.

The 122-metre (400-foot) ship is capable of continuously breaking ice up to 1.8 metres (six feet) thick while travelling at three knots, and can break ice more than six metres thick by ramming.

It is expected to take seven days to reach Commonwealth Bay where the two ships are trapped, 100 nautical miles from the French Antarctic base of Dumont d'Urville.

The stranding of the Shokalskiy, which was carrying 22 scientists, 26 paying passengers and four journalists as well as 22 crew who remain on board, has sparked criticism in some quarters.

As well as the Xue Long and Polar Star two other icebreakers, Australia's Aurora Australis and France's Astrolabe, were diverted from their Antarctic missions to assist the Shokalskiy.

Yves Frenot, director of the French Polar Institute said the rescue saga had forced French scientists to scrap a two-week oceanographic campaign using the Astrolabe.

"But we are relatively lucky. The Chinese have had to cancel all their scientific programme, and my counterpart in Australia is spitting tacks with anger, because their entire summer has been wiped out," he said.

The Australis was forced to suspend its resupply of the Australian base to rush to the aid of the Shokalskiy, but authorities said it was not yet known what impact the incident would have on scientific programmes.

Chris Turney, leader of the Shokalskiy's expedition which repeated century-old measurements to explore environmental changes as it retraced a 1911-14 voyage of the Antarctic, hit back at Frenot's criticism.

"Yves was fully aware of the expedition and there was even an exchange of emails around it in September. At no time did Yves indicate any problems with the science of the expedition or the expedition itself," Turney told AFP.

"The science on the expedition was supported by a number of major research institutions including NOAA (US National Oceanic and Atmospheric Administration), the University of Wisconsin and a host of others."

Turney said there was a long history of both governmental and private vessels going to the assistance of others in the Antarctic.

The Auora Australis is now en route to Australia's Casey Antarctic base to complete a resupply run, from where it will return to Hobart, with Turney and the Shokalskiy's other passengers on board, later this month.

Chinese ship used in Antarctic rescue stuck in iceSydney (AFP) Jan 04, 2014
A Chinese icebreaker that went to the aid of a Russian ship stuck in heavy floes in Antarctica has now itself become trapped by ice, officials said Saturday, amid anger about the impact of the rescue on research.
The Xue Long, which on Thursday used its helicopter to ferry dozens of passengers on the stranded Russian ship Akademik Shokalskiy to the safety of an Australian vessel, has been un ... read more

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